Technical Abstract:
Contamination of poultry vaccines with adventitious agents (i.e. reticuloendotheliosis virus, chicken anemia virus) has been previously reported. Contaminating agents may be introduced at various stages during production, whether through propagation systems or shared equipment. Contamination of inactivated, oil emulsion poultry vaccines with avian influenza virus (AIV) is one such concern. Although these are inactivated vaccines, therefore eliminating the threat of disease, because of the wide-spread use of antibody screening to assess poultry flocks for exposure to AIV, detection of AIV antibody in a flock can have serious economic consequences. Additionally, some countries (i.e. Peru) currently require that imported poultry vaccines be screened for AIV contamination. Detection of contaminating agents in inactivated vaccine preparations can be difficult because culture methods can not be used. Contaminants can be detected either indirectly by detection of antibody in vaccinated birds, or directly, by detection of viral proteins or viral nucleic acid. However, common sample processing procedures for nucleic acid based assays can not be used with oil emulsions. We describe a new method of RNA extraction and detection of influenza viral RNA using real-time RT-PCR technique. This technique appears to be a rapid and sensitive method of detecting avian influenza in inactivated, oil emulsion vaccines.